Honing machine



Minh 26, 1940 L` G. cRoMToN, JR., Er AL 2,194,821

HoNING MACHINE Filed Aug. 19, 1938 2 Sheets-Sheet l lz/MU H 5.4 HUN ,2i400 127 H615?) G50/QSE CRUMPTDN, LIR.' 8] THEUDDRE H. NYE

[-75, Z MM' Elx/imma@ March 26; 1940. G. cRoMPToN, JR., Er AL 42,194,821

l I HONING MACHINE I Filed Aug. 19, 1938 2 Sheets-Sheet 2 GEORGECRDMPTQN,=JR. THEDDDRE H. NYE

Patented Mar. 26,1949

UNITED STATES HONING MACHINE George Crompton, Jr.,

and Theodore H. Nye,

Worcester, Mass., assignors to Norton Company, Worcester, Mass., acorporation of Massachusetts Application August 19,

17 Claims.

The invention relates to honing machines, particularly for honinginternal cylindrical bores.

One object of the invention is to provide a sim,. ple apparatus wherebythe several bores of ay cylinder may be brought to the same size within.close limits. Another object of the invention is to provide apparatusfor honing cylinder bores with provision for automatic adjustment of thehoning tools. Another object of the invention is to provide an improvedmethod for the continuous adjustment of radially expanding honing tools.Another object of the invention is to provide automatic adjustment meansfor honing tools capable of being applied toexisting machines. An-

other object of the invention is to provide apparatus which takes theguess-work out of honing tool adjustment. Other objects will be in partobvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction,combinations of elements, and arrangements of` parts, and in the severalsteps and relation and order of each of said steps to one or more of theothers thereof, all as will be illustratively described herein, and thescope of the application of which will be .indicated in the followingclaims.

In the accompanying drawings illustrating one of many possibleembodiments of the mechanical features of this invention,

Figure 1 is a side elevation of a honing machine constructed inaccordance with the invention, certain parts being shown in section;

Figure 2 is a horizontal sectional view taken on the line 2-2 of Figure1;

Figure 3 is a horizontal sectional view taken on the line 3 3 of Figure1;

Figure 4 is a pneumatic diagram;

Figure 5 is a front elevation of a portion of the machine shown inFigure 1, certain parts being shown in section;

Figure 6 is a vertical axial sectional view of a honing tool which isarranged to be automatically adjusted according to the invention;

Figure 7 is a horizontal sectional view taken on the line 1-1 of Figure6. The invention may be incorporated in a Vhoning machine of the typedescribed in U. S. Letters Patent No. 1,783,019 to Albert M. Johnson. Infact, machines already constructed according to this patent (hereinafterreferred to` as the Johnson patent) may be changed over with theaddition of certain mechanisms vherein described to operateautomatically or semi-automatically according to the present invention.The invention is disclosed in connection with a honing tool, such 1938,Serial No. 225,686

as shown in the patent to Fred M. Kern No. 1,927,-

I 039 (hereinafter referred to as the -Kern patent).

However, the invention may readily be adapted to operate in connectionwith other types of honing tools.

As in the case of the Johnson patent, and referring now to Figure 1',the machine comprises a 'base I upon which is fixed an upright column 2frontwardly provided with a pair of vertical slideways 3. A piece ofwork is shown supported on the base Icomprising in the present instancea four-cylinder internal combustion motor block 6 clamped in anysuitable manner, not shown,

' upon an adapter block 'I which rests upon a dat surface of the base I.y

Referring to Figures 1 and 5, mounted upon the upper end 'of the column2 is a main housing 8 having a pair of upright auxiliary housings 9 andI0. The auxiliary housings 9 and IIJ each support a verticallypositioned spindle driving shaft II. 'I'he spindle driving shafts II arejournalled in guidesleeves It reciprocably mounted in theA auxiliaryhousings 9 and I0. On the upper end ofthe housing 9 is a gear casing 9alwhile on the upper end of the housing I0 is a similar gear casing, notshown. By means of gearing contained within these gear casings and'further gearing contained within the Amain housing 8- and the auxiliaryhousings 9 and I0, the spindle driving shafts II are rotated all at thesame angular velocity. At the sainetime, owing to the`fact that theshafts II are splined, as clearly shown in Figure 1, and fit in gearsleeves, not shown, the rotary drive to the spindles II vin no wiseinterferes with their vertical .reciprocatory movement. Thisdrivingmechanism together with clutch and brake device will be foundmore fully described in the Johnson patent. The Johnson patent alsodescribes fluid pressure Aactuating mechanism for moving the guidesleeves in unison up and down. Controlling apparatus for the fluidpressure reciprocating mechanism is provided whereby, at the will of theoperator, the sleeves Il may be caused to descend, to reciprocate in alower range, and to rise above this lower range at will. Such apparatuswe shall not describe herein since reference may readily be made to theJohnson patent. Some of the controls described in Cromptons copendingapplication Serial No. 219,988flled July 19, 1938 may also be used ifdesired.

Still referring to Figures 1 and 5, suitably attached lto the sleevesIl'is a head 20. This head moves up and down in unison with the sleevesI4 and journals a plurality of spindles 2| mounted in parallel relation.By gearing in the head 20 which is fully disclosed in the Johnson patentreferred to, all four of the spindles 2| are driven` at the same speedand in the same direction, the right-hand pair being driven by theright-hand spindle |I and the left-hand pair being driven by theleft-hand Vspindle il.

Referring now to Figure 6, we provide a plurality of honing tools 25which may be of substantiallyl the same construction as illustrated anddescribed by the Kern patent. As reference may be readily had to theKern patent, we shall only briefly describe some of the major parts ofthe honing tool 25 herein. As shown, the tool includes a lower spindle26 and an upper spindle 21. Each spindle 2| has a bayonet socket 30 atthe lower end thereof which receives a trunnion pin 3| projectingthrough spherical members 29 located in the internal bore 22 of thespindle 2|. The pin 3| also passes through the upper spindle 21 andthereby holds the entire honing tool 25 to the spindle 2|, thisconstruction constituting a universal joint.

The spindle 21 is connected to the spindle 26 by means of a universaljoint 32. The spindle 26 supports an upper spider 33 and a lower spider34, which spiders guide holders 35 and 36 supporting metal carriers 31in which are set abrasive stones 38. The abrasive stones 38 which may bemade of any suitable abrasive material, such as alumina or siliconcarbide bonded with organic or vitried bond, are thus mounted for radialmovement in the tool 25. Removable garter springs 40 tting overprojecting hooks 4| of the metal members 31 bias the holders 35 and 36and the abrasive members 38 inwardly and hold Vthese parts in assembledrelation.

The upper portion of the spindle 21 is threaded and thereon are a pairof nuts 41 and 48 which are relatively movable for providing a lockingengagement Vfor longitudinally positioning a cam carrying collar 50mounted on a sleeve portion 41a of the nut 41. Between the flange of thenut 41 and the collar 50 are a plurality of washers 49 for reducing therotational friction between the members when adjustment is made. At thelower end ofthe collar 50 are formed a plurality of pairs of earsbetween which extend pins 52'journalling cam levers 53. We form thesecam levers 53 with elongated upper ends 54 so that they may be operatedfrom the top as well as from the bottom.

The lower ends of the cam levers 53 engage a conical cam surface 55.0f athrust collar 56, the lower surface of which engages steel balls 51mounted in a ball cage 58. The balls 51 rest on an adjustment collar 59seating in spherical depressions 50 thereof which are shown in Figure'1. The adjustment collar 59 is internally threaded and mounted on theexteriorly threaded portion of a sleeve 6| which is journaled on theunthreaded portion of the spindle 21. 'Iyhe sleeve 6| is an integralpart of a housing 62 which encloses a spring cage 63 holding a powerfulspring 64 under initial compression. A shoulder 65 of the housing 62 ispositioned to engage the upper end of the spring 64/as clearly shown inFigure 6. The lower end of the cage 63 rests on a plurality of washers 66, the lower one of which engages a pair of thrust rods located ingrooves in the spindle 26. These thrust rods 10 bear against anactuating member 1I having three sets of conical surfaces positioned toengage wedge portions on the holders 35.

By means of this construction, which is more fully detailed in the Kernpatent, whenever the cam levers 53 are compressed inwardly (there beingusually three of such cam levers), the thrust collar 56 is depressedwhich forces downwardly the adjustment collar 59, thereby movingdownwardly the housing 62ywhich, through the spring 64, depresses thethrust rods 10 which moves downwardly the actuating member 1|, therebyexpanding the holders 35 and 36. The reacting thrust is, of course,taken through the pins 52 to the collar 50 to the nut 41 to the spindle21, thence through the universal joint 32 to the spindle 26, thence tothe spiders 33 and 34 which hold the holders 35 and 35 from downwardmovement. The stones or abrasive sticks 38 are directly expanded in thismanner unless they are positively prevented from expanding by a pressurewhich will overcome the initial tension of the spring 64 backed up bythe mechanical advantage inherent in the cone and wedge actuating means.The exact effective diameter of the sticks 38, however, is dependententirely upon the adjustment of the collar 59. We provide ratchet teethon the periphery of the adjustment collar 59 for automatic actuation ofthis collar automatically to adjust the several tools.

Before describing the features which are more especially our presentinvention, as rconducive to a better understanding thereof, we will nowmention a common manner of operating the machine tool of the Johnsonpatent equipped with honing tools of the Kern patent. It has beencustomary to provide a set of sleeves just above the bores of thecylinder block being honed throughl which the honing tools pass andwhich compress the cam levers 53 when the honing tools are down. Inmachine tools so operated, the hones are collapsed when the head is upand are expanded by the action of these sleeves just after the toolsenter the several bores of the cylinder block being honed. At the end ofa particular honing operation on a particular cylinder block, theoperator has adjusted the collars 59 by an amount suiiicient in hisjudgment to account for wear of the sticks 38` or to bring the bores ofthe next cylinder block to the desired size. In tools so operated,however, cylinder bores of the cylinder blocks have varied in finaldiameter so that as many as five different sizes of pistons have beenprovided in regular automobile production to match the diiferent sizedbores.

According to our present invention in one of its aspects, we provide twosleeves above each engine cylinder bore into the lower one of which weexpand the hone when it is in its upper position by compressing the camlevers 53 with the upper of such sleeves. We further cause an automaticdevice to move the adjustment collar 59 to expand the particular honeuntil substantial resistance is met with` Thereby the honing tools areautomatically set so that they will ultimately expand in the cylinderbores to the required or desired diameter and the adjustment is notdependent upon guess-work but is a predetermined adjustment. Since thesleeves which we provide may be slightly larger in diameter than thebores to be honed, we may thereby allow for wearing of the honing sticksduring a particular honing operation. This reduces the vari able to thedifference in wear of the honing sticks during successive operations,which is a much smaller quantity than the total amount of wear.

Referring again to Figure 1, We provide a plu rality of metal sleeves 8Usupported in a single bracket 8| slidably mounted for verticaladjustment on the ways 3 and rigidly clamped in adjusted position in anysuitable manner, as by means of bolts 82. embodiment of the invention,in which there are four bores in the cylinder block 6, there are foursleeves 80 spaced the same as the bores in the cylinder block. Inaccordance with considerations above mentioned, the internal diameter ofthe sleeves 80 is slightly larger than the ultimate desired size of thework pieceibores. In order that the cam levers 53 may readily enter thesleeves 80, and in order to avoid fracturing of the abrasive sticks orstones 38, the sleeves 80 are bell mouthed at both ends, as shown.

We further provide, as also shown in Figure 1, four sleevesl 85 ofinternal diameter the same as the sleeves 80 and bell mouthed on thelower ends. These sleeves 05 are mounted in a bracket 86 which isslidably mounted on the ways 3 and adapted to be clamped in any positionof adjustment, as by means of bolts 81. Figure 1 shows the honing partof the tool 25 located in the sleeve 80 while the cam levers 53 arelocated in the sleeve 85. If then at this point the adjustment collar 59be moved to eliminate any space between the spring 64 and the shoulder65 and also any space between the sticks 38 and the sleeves 80,thereafter when the tool 25 is lowered into the bore of thel work piece6, it will be expanded by engagement of the sleeve with the cam levers53 and, since the bore in the work piece 6 must be somewhat under size,the spring 64 will be slightly compressed within its cage 63 and lateron, when the cage 63 contacts the spring 64, the work piece will havebeen honed to predetermined size, which will be the same as the internaldiameter of the sleeve 80 less wear of the abrasive sticks during thatparticular honing operation. Since thc adjustment collar 59 may beeasily turned with the fingers to take out backlash in the' parts, or tocompress a weak mined initial tension. Such apparatus in the presentillustrative embodiment of our invention comprises multif-toothed pawlsoperated by cylinder and piston apparatus energized by pneumatic orsteam pressure.

Referring now to Figure 4 which, excepting for the pipe connections, isnot wholly diagrammatic, we provide aplurality of cylinders |00, one foreach honing tool 25, which would be four in the present embodiment.,These cylinders |00 may be mounted on a suitable ledge |0| provided onthe inside of the column 2 and fastened to this ledge. But in the caseof changing over old machines, these may be mounted in front of themachine on a suitable stand or bracket. Each cylinder |00 is' providedwith a piston |02 mounted on alpiston rod |03. 'I'he piston rods |03project forwardly through cylinder heads |04 which, with rear cylinderheads |05, close the ends of the cylinders |00. As shown in Figure 1,the piston rods |03 likewise project through holes formed in the, frontwall of the column 2.

We provide on the front of each piston rod |03 a multitoothed pawlmember I0. These may be in the form of bars with yratchet teeth. EachIn` the present illustrative pawls ||0.` The articulation joints are soformed that the pawls ||0 cannot move in ar counterclockwise directionbeyond the positions shown in Figure 4 and also in Figure 1, but thejoints permit movement of the pawls ||0 in a clockwise direction.

| I2 bolted by bolts ||3 to the piston rods |03 and engaging the pawlmembers |0 normally to hold the pawl members in the straight lineposition shown. These springs ||2, however, permit the pawl members 0 toswing backwardly for a limited distance, that is to say in a clockwisedirection, Figure 4.

The`cylinders |00are so located that the pawl members ||0 are inposition to engage theratchet teeth 15 upon a forward movement. of thepistons |02. We provide a pneumatic mechanism resiliently to urge thepistons |02 forwardly whenever the tail pieces 54 of the cam levers 53engage the sleeves 85. Referring now to Figures 1, 3 and 4, we provideva valve block |20 secured to the column 2, adjustably if desired. Wefurther provide a valve operating abutment |2 secured to the head 20.Referring to Figure 4, the valve block |20 has chambers |25, |26, |21and |28. In the chambers |25 and |26 are conical seats to seat poppetvalves |29 and |30. These waives |29 and |30 are normally maintainedagainst their seats by means of springs |3| and |32. In the chamber |21and |28 we provide puppet valves |33 and |34. In the upper parts of thechambers |21 and |28 are conical seats to fit the valves |33and |34 butsprings |35 and |36 vnormally hold the valves |33 and |34 away from theseats in the chambers |21 and |28.

Weprovide a pipe |40 connected to a suitable source of pressure. Whileliquid pressure may be used, especially in connection with a reliefvalve, we prefer to use gas pressure because of re- We provide ngersprings siliency of its action. In our preferred embodii ment, we useair pressure. The pipe |40 leads to the upper end of valve chamber |25and a branch |40a' leads to the upper part of the valve chamber |21.

In the lower part of the chamber |21 is a port |4| connected by a pipe|42 to a( throttle valve |43 connected by a pipe |44 to az pipe |45having branches |4541` leading to the front ends of the cylinders |00.Figure 4 indicates the parts prior to the' time when the cam levers 53enter the Whenever the head 20 is in its uppermost position, as shown inFigure 1 the abutment member |2| is in engagement with the valves |29and |30 and these are consequently open. dentally the valves |33 and |34are closed, the valve stems thereof being engaged respectively-byplungers |50 and |5| carried bythe abutment Coincimember |2| but backedupby springs |52 and |53. Under such conditions pressure is cut olf fromthe pipe |42 and the exhaust through the f pipe |46 is likewise cut oif.The valve |29 being in its upper position, connects the pressure to aport |55 which is connected by a pipe |56, throttle valve |51 and pipe|58 to the pipe |46. This opens the pressure to the right-hand ends-ofthe cylinders |00. Poppet valve |30 being up, connects an exhaust "port|60 to a pipe IBI which is connected to the pipe |45. This allows theair to exhaust from the front ends of the cylinders |00.

In operation this mechanism normally maintains the multi-toothed pawlsin their rearward positions, as indicated in Figure 4. Figure 1 showsthe parts with the valves |33 and |34 closed and the valves |29 and |30opened and the cam levers 53 in the sleeve 85. The pistons |02,therefore, have moved forwardly. In so doing, the multi-toothed pawlmembers ||0 have engaged the teeth 15 and rotated the adjustment collars59. The action, however, is a resilientl or` non-positive one and somecollars may have been rotated more than others. Whenever the head 20moves downwardly, the pawls ||0 are all of them retreated. Usually thisaction will not occur until the adjustment collars 59 have moved belowthe multi-toothed pawl members ||0, but at all events these pawl membersmay move in retrograde direction on the teeth 15 without eiect on theadjustment since the pawl members ||0 are mounted to swing outwardly.Furthermore, the balls 51 and seats 60 act to prevent any retrogrademotion of the parts of the honing tool.

In operation the honing tools 25 are expanded by the sleeves.85 to thesame extent that they are expanded by the sleeves 80. But subsequent toa particular honing operation there will be a variable amount of slackto be taken up in each honing tool so that the next work piece may bebrought tothe desired size. This adjustment is automatically effected bythe non-positively operated multi-toothed pawls ||0 which actautomatically whenever the head 20 reaches its uppermost position.

It is preferred that when the multi-toothed pawls ||0 are movedforwardly to engage the ratchet teeth 15, the honing tools 25 haveceased their rotation. In the machine of the Johnson patent referred to,the rotation can be stopped manually. However, automatic apparatusautomatically to stop the rotation of the honing tools when the head 20rises is disclosed in the copending application Serial No. 219,988previously referred to. In any event we prefer that the multi-toothedpawl ||0 be on that side of the ratchet teeth 15 which it is to operateso that rotation of thetool moves the teeth in the same direction thatthe pawl does. Under such circumstances, if there is slight residualrotation to the tool when the pawl acts, this will not break any partsand nevertheless the pawl will perform the desired operation by reasonof the fact that its linear velocity can readily be made greater thanthe peripheral velocity of the ratchet teeth under such circumstances.For example, the operator has merely to adjust the throttle valve |51until the pawls move fast enough to effect the adjustment under allconditions of operation.

According to certain of its aspects the invention may be embodied inapparatusherein disclosed, omitting the cylinder-piston units |00, |02with the pawls H0 and the valve mechanism described. lOwing to theprovision of the two sleeves 80 and 85 for each honing tool; theoperator himself may more readily and accurately adjust the honing toolsafter each honing operation and our invention is to be deemed to include this apparatus whether with or without the automatic ratchetadjustment.

It will thus be seen that there has been provided by this invention amethod and apparatus l in which the various objects hereinabove setforth together with many thoroughly practical advantages aresuccessfully achieved. As manylpossible embodiments may be made of theabove invention and as many changes might be made in the embodimentabove set forth, it is to be understood that all matter hereinbefore setforth or shown in the accompanying drawings is to be interpreted asillustrative and not in a limiting sense.

We claim:

1. In apparatus' of the class described, a honing tool, expansiblecarriers for honing sticks in said honing tool, cam levers to expandsaid carriers, a mounting for said honing tool permitting it to be movedrectilineally, and a pair of sleeves to actuate said cam levers andexpand said carriers spaced apart substantially the same distance as thecam levers are spaced from the carriers whereby onesleeve will compressthe cam levers to expand the carriers in the other sleeve.

2. In honing apparatus, a rotatable honing tool, a mounting permittingsaid tool to be moved rectilineally, a support for a work piece, a rstsleeve, a second sleeve, the two sleeves being in axial alignment witheach other and with the honing tool, and the work holder being formed tohold a work piece with a bore in axial alignment with said sleeves andsaid honing tool, said tool having carriers for abrasive sticks in saidhoning tool mounted for expansion, and means including cam levers toexpand said carriers and Vspaced in an axial direction on the honingtool some distance from vthe carriers, so that when the cam levers enterthe second sleeve the carriers are expanded in the rst sleeve and whenthe cam levers enter the rst sleeve the carriers are expanded in thework piece.

3. In apparatus as claimed in claim 2, the combination with the partsand features therein specified, of take-up adjustment means between thecam levers and the carriers whereby the parts may be adjusted for 'wearwhen the cam levers are in the second sleeve and the carriers are in therst sleeve so that the carriers will expand to a given predeterminedamount in the work piece when the cam levers are in the rst sleeve.

4. In apparatus of the class described, a honing tool having a loweroperating position and an upper remote position and mounted to moverectilineally through such positions, means to rotate said honing tool,carriers for abrasive sticks in said honing tool mounted for` radialmovement, members and connections whereby to expand said carriers whensaid members are actuated, means to actuate said members when saidhoning tool is in the remote position, means to adjust the connectionsat such moment whereby to predetermine the ultimate size of work piecebores, and gauging means contacting the abrasive sticks when the honingtool is in the remote position to procure the adjustment to a vgiventotal expansion of the abrasive sticks.

5. In apparatus of the class described, the combination with a honingtool comprising spindle 'meanls, holders mounted for. movement of exist4mote from said holders, a thrust collar operated by said cam levers, andconnections between the thrust collar and the holders including a nutand a screw for adjustment, of. automatic means to move the nut atpredetermined intervals.

6. In apparatus of the class described, the combination with a honingtool comprising spindle means, holders mounted for movement of expansionand contraction relative to said spindle means, abrasive sticks securedto said holders, cam levers mounted on said spindle means remote fromsaid holders, a thrust collar operated by said cam levers, andconnections between the thrust collar and the holders including a nutand a screw for adjustment, of pawl and ratchet means to rotate the nutand piston and cylinder means to move the pawl at predeterminedintervals.

'7. In apparatus of the class described, the combination with a honingtool comprising spindle means, holders mounted for movement of expansionand. contraction relative to said spindle means, abrasive sticks securedto said holders, cam levers mounted on said spindle means remote fromsaid holders, a thrust collar operated by said cam levers, andconnections between the thrust collar and the holders including a nutand a screw for adjustment, of a pair of. sleeves in axial alignmentspaced so that the cam levers may enter one sleeve while the holders andabrasive sticks are in the other sleeve and automatic means to rotatethe nut at such stage with a resilient pressure.

8. In apparatus of the class described, a honing head, a mountingpermitting said honing head to be moved rectilineally, a plurality ofspindles in parallel relation carried by said honing head, the axes ofthe spindles being parallel to the line of movement of the head and thespindles being mounted for rotation, a honing tool carried at the remoteend of each spindle and each honing tool comprising holders yforabrasive sticks, mountings for the holders holding the sticks inparallel relation and permitting expansion and contraction, cam leversremote from the holders, an adjustment ring, a screw threaded memberupon which said adjustment ring is mounted, connections from the camlevers through the adjustment ring to the holders whereby when thecamlevers are compressed the holders are expanded, a set of. sleeves remotefrom the head whose axes are all parallel to each other and to thespindles and are in axial alignment y with the spindles and of a size toactuate the cam levers to compress them when the holders are in workpiece bores to expand the abrasive sticks to ei'ect a honing operation,anda second set of sleeves in` axial alignment with the rst set, of thesame size and betweenthe iirst set and the head whereby to actuatethecam levers and expand the holders, pressing the stick against the wallsof the rst sleeves.

9. In apparatus as claimed in claim 8, the combination with the partsand features therein specified, of automatic means to operate theadjustment ring when the cam levers are in one set of sleeves and theholders are in the other set of sleeves to take up all the back play atsuch time. 10. In apparatus as claimed in claim 8, the combination withthe parts and features therein specied, of ratchet teeth on theadjustment rings, a plurality of pawls to actuate the ratchet teeth, andresilient means to actuate the pawls.

11. In apparatus as claimed in claim 8, the

combination with the parts and features therein specied, of a pluralityof cylinders and pis'- tons, a source of fluid under pressure, valvemeans to connect the several cylinders to the pressure fluid, said valvemeans being automatically operated when cam levers are in the sleevesnearest the head, and devices connected to the pistons to operate theadjustment rings at such time.

12. In apparatus of the class described, the combination with a spindlemounted for rotation and for rectilinear movement to advance, Withdrawand reciprocate, a honing tool mounted at the end of said spindlecomprising radially mounted parallel holders for abrasive sticks,apparatus to expand said holders,.and adjustable connections between theholders and the apparatus, of means to actuate the apparatus to expandthe holders when the spindle is reciprocating, and additional lmeans toactuate the appayratus to expand the holders when the spindle iswithdrawn, said two last namedmeans permitting the holders to becontracted when the spindle is advancing and withdrawing, the entireapparatus including gauging means to, gauge the expansion of theabrasive sticks when the spindle is withdrawn whereby to settheapparatus to bring a work piece bore to desired size within the limitsof variability of wear of the honing sticks in a particular honingoperation.

13. In apparatus of the class described, a -honing head, a plurality ofparallel spindles mounted in said honing head, means to rotate saidspindles, means to move said head rectilineally, a honing tool mountedin each spindle and including holding members for abrasive sticksmounted for expansion and contraction in parallel relation, actuatingdevices, adjustable connections from said actuating devices to saidholders whereby to expand said sticks, means for actuating all of theactuating devices when the honing tools are outside of the bores of awork piece, means for gauging the amount of expansion of the abrasivesticks at such time, and means for adjusting the adjustable connectionsat such time to expand each of the honing tools to a predeterminedamount, the apparatus including also means for actuating the actuatingdevices when the honing tools are in the bores of a work piece wherebythe adjustment with the tools outside the work piece 'gauges the toolsfor bringing the bores to a desired size;

14. Apparatus of the class described comprising a honing head mountedfor rectilinear movement, a plurality of spindles carried in parallelrelation by said honing head and mounted for rotation, honing toolscarried by said spindles, said honing tools being capable of expansionand contraction, adjustable devices to expand said honing tools wherebythe amount of expansion ofthe tools may be adjusted, a plurality ofnonpositive automatically actuated means to adjust the adjustabledevices, and gauging means to gauge the amount of adjustment at suchtime whereby to bring all of the hones to a given setting relative totheir effective diameter in view of wear on the abrasive sticks.-

15. In apparatus of the class described, a honing tool having a loweroperating position and an upper remote position and mounted to moverectilinearly through such positions, means to rotate vsaid honing tool,carriers for abrasive sticks in said honing tool mounted for radialmovement, members and adjustable connections whereby to expand saidcarriers when said members are actuated, means to actuate said mem-vbers when said honing tool is in the remote position, and gauging meansto measure the expansion of the carriers by contact with the abrasivesticks whereby the connections may be adjusted to cause a givenexpansion of the sticks to result from a given actuation of the members.

16. In apparatus of the class described, a honing head mounted to moverectilineally, a plurality of spindles mounted in said head, means torotate al1 of the spindles, honing tools carried by the spindles,sleeves approximately the size of work piece bores to limit theexpansion of the honing tools, devices on the spindles which Whenactuated expand the honing tools, take-up adjustments for said devices,means to actuate the devices, and means to actuate the take-upadjustments, said last two means being operated when the honing toolsare in the sleeves whereby to expand the honing tools to a given amountto predetermine the diameter of work piece bores.

17. In apparatus of the class described, a honing tool comprising aplurality of abrasive sticks mounted in parallel arrangement to dene acylinder, means mounting the sticks permitting radial movement,adjustable means to move the GEORGE CROMPTON, JR. THEODORE H. NYE.

